1. Field of Invention
The present invention relates to an axially actuating device having an elastic joining portion, and more particularly, to an axially actuating device applied in a digital image-capturing device.
2. Related Art
Generally, driving devices that are convenient for carrying along and available for be used at any time have the characteristics of being small, light, and chic, and on the other aspect, it is easily dropped off due to incautiousness, which thus damages the inside mechanism or the function is not desirable. Therefore, the dependence on a protecting device is essentially increased, but the addition of the protecting device results in increasing of the number of parts, and thus increasing the volume and weight and becoming inconvenient for reserving, so that the original advantages are not existed any longer. Moreover, from the designing view of being light, thin, short, and small, the decrease in size enhances the difficulty in assembling, so that the cost is increased.
The motor is widely used as a portable electronic device, and the growing speed of the number of motors applied in the current portable electronic equipments such as a digital camera has continuously exceeded that of voice coil motors and spindle motors applied in a hard disk driver conventionally. Nowadays, the development of the motor must satisfy the strict miniaturization trend requirements. The conventional voice coil motors have substantially the same structure, which generally consist of components such as a coil, a magnet, and a yoke. The largest difference between structures of conventional voice coil motors lies in the joining component for combining the moving portion with the fixed portion, since a complete actuator can be assembled only through the joining component.
The joining device generally includes the following types, which all have disadvantages as follows. 1. Spring-type joining device is performed in the way of pressing the brush by a spring. The axial length is too long to satisfy the miniaturization requirement, and since the mechanical spring has a large coefficient of rigidity, a large elastic force should be overcome. 2. Linear bearing-type joining device, contrary to the spring-type joining device, occupies an extreme large space in the radial direction, and a positioning device is required to control the displacement. 3. Leaf spring-type joining device, a commonly used joining component in the market, occupies a small space, and thus satisfying the miniaturization requirement. However, the most significant disadvantage of the leaf spring-type joining device lies in that, a small amount of rotating movement is made in the axial direction, and the shock proofing efficacy is not provided, and thus not suitable for a product that is liable to be dropped out.